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1.
Analytical data for minor and trace elements published or communicated to us, on seventeen GSJ (Geological Survey of Japan) reference samples, "Igneous rock series" received up to April 1994 are compiled. The data were evaluated statistically in consideration of analytical methods. Based on the selected available data, 1994 recommended and proposed values for 65 minor and trace elements are presented.  相似文献   

2.
All data reported by 200 analysts (106 laboratories) are presented for the four ANRT samples: Diorite DR-N, Serpentine UB-N, Bauxite BX-N and Disthène DT-N. Recommended values are given for the major and minor elements. As far as the as trace elements are concerned, DR-N has been characterized for 35 elements whereas the other three samples have been for only 20 elements. Wherever possible, brief comments have been inserted so as to explain our way of assigning recommended or proposed values.
After more than a decade of existence the total number of data reported for all the four samples reach only 3200 units which are not sufficient enough for a valid evaluation of compiled data. It is also pointed out that these samples are most likely to be available even during the next century as they have been prepared in large quantities of the order of one ton. A plea is therefore made for contribution of more data particularly for trace elements and for major elements which are present as trace elements in UB-N, BX-N and DT-N.  相似文献   

3.
Analytical data for five GSJ (Geological Survey of Japan) reference samples, the "Instrumental analysis series" received by October 1998, are compiled. The data reported in publications and personal communications were evaluated statistically, taking into account the analytical method and sample preparation. Based on the selected available data, recommended and preferred values for fourteen major and fifty one minor and trace elements are proposed.  相似文献   

4.
Reliable rock reference materials for Au, Pd and Te are scarce. We report here our analytical data on these three elements in 46 NIM, IGGE and GSJ reference samples in order to accumulate analytical data on these samples.  相似文献   

5.
The results are given for all the determinations made by the co-operating laboratories of major elements in the six NIMROC rock samples (granite, syenite, lujavrite, norite, pyroxenite and dunite) prepared by the National Institute for Metallurgy in 1966. Relevant statistical data are given for the sets of results for each major constituent, and recommended values for all constituents except Al203, Na20, K20and CO2 in dunite, Fe2O3, MgO and CO2 in the granite, Fe23 and CO2 in the norite and CO2 in the pyroxenite.
This report and that on the trace and minor elements issued in 1978 complete the revision of the recommended values. It is suggested that analysts should concentrate rather on those constituents for which the results have shown such a wide scatter that they can be of no usc for reference purposes, than on those for which the ualues are fairly well established.  相似文献   

6.
During the five-year period (April 1981 - March 1986), a series of fifteen rock reference samples, "Igneous rock series", has been prepared by the Geological Survey of Japan (GSJ). Based on the data available (published and communicated), consensus values for major, minor and trace elements have been derived; these values are presented for this second series of samples as well as for the first series of two samples, Granodiorite JG-1 and Basalt JB-1.  相似文献   

7.
The 18 Chinese geochemical standard reference samples GSD 9-12 (stream sediments), GSS 1-8 (soils) and GSR 1-6 (rocks) were prepared after GSD 1-8 (stream sediments) for even wider and increasing needs of geology, exploration geochemistry and geochemical analysis. Usable values of 41 trace, minor and major elements of the 18 samples were published in 1984. In the following two years, efforts were concentrated on the determination of other elements, most of which are more difficult to determine accurately and hence not many data were available in the literature. At the same time, additional data on the 41 elements already evaluated were also submitted. In all, 155 234 results were available along with the 35 284 analytical data submitted. The processing of samples, the examination of sample homogeneity, the plan of collaborative analysis of the samples, and the criteria for defining the recommended values are described. The recommended or reference values of the 72 constituents, to-gether with the 35 284 analytical data of the 18 samples are published in this paper.  相似文献   

8.
60 geochemical laboratories from the world over, contributing in all 3687 bits of chemical data on 60 elements, haue willingly participated in the study of SOIL-5 as a reference material. The preparation of SOIL-5 in 45 kg and homogeneity teats are described; in addition, all the data compiled are presented. In evaluating the compiled data, the use of four concurrent tests for outlier-rejection at the same level of significance, has been applied. After proper statistical treatment, “recommended values” could be established for 31 elements, most of them trace elements and “information values” for 29 elements. 23 of the recommended values could be given with a “relatively high” degree confidence whereas the other 18 recommended Values with a “reasonable” degree of confidence. An attempt is made to compare the analytical methods employed; the existence of possible sy3tematic differences is pointed ont.  相似文献   

9.
A solvent extraction, flame atomic absorption analytical scheme is reported for the elements Au, Tl, Sb, Ga, Mo, Cu, Ni, Co, Ag, Bi, Cd, Pb, Zn and Mn in geological materials. Results are quoted for NIM standard rocks and for USGS reference samples, and are compared with published values; practical detection limits are generally better than 0.2 ppm. A stepwise solvent extraction and preconcentration process is utilised (chloro complexes, diethyldithiocarbamate and 8-hydroxyquinoline chelates are used with methyl isobutyl ketone and n-butyl acetate as solvents) which allows the reproducible isolation of groups of elements which generally occur at similar concentrations geologically. Analytical accuracy is maintained by the chemical elimination, within each step, of other chelate-forming elements present at higher concentrations which would cause spectral interferences during the atomic absorption measurements. The complete stepwise process is reported together with elemental partition data which covers a range of aqueous ionic conditions.  相似文献   

10.
The six ANRT rock reference samples (DR-N, UB-N, BX-N, DT-N, GS-N, FK-N) have been distributed as reference samples for nearly twenty years. All available data on trace elements in these samples are presented and evaluated. It has been possible to assign working values for nearly 40 trace elements. These samples prepared in 600 to 1300 kg quantities are expected to last for some decades to come.  相似文献   

11.
The first report (1980) on the three samples, Anorthosite AN-G, Basalt BE-N and Granite MA-N resulted in the chemical characterization of major, minor and 30 trace elements. The present report confirms the validity of a great majority of these working values, in addition to presenting working values for 20 more trace elements for each sample. Only compiled data on trace elements are presented, followed by Tables of statistical parameters used as a basis for their evaluation, both statistical and subjective. A plea is made to obtain more data on platinum group elements and on other "difficult" trace elements (Au, B, Bi, Se, Te, TI, …). The three samples have been processed in 900 kg amounts and, therefore, they are likely to remain available for some decades to come. As such, it is certainly worthwhile to take pains to characterize them well for even these difficult trace elements.  相似文献   

12.
Trace element data compiled on, geoshemical reference samples present invariably skewed distributions. It is proposed to treat such data as lognormally distributed and to compute geometric means (Xgm) as probable values. As examples, the Xgm values derived for some trace elements in some rock reference samples are compared with the "recommended" values and with the "gamma" values of Christie.  相似文献   

13.
Analytical data for 31 elements in 8 Japanese, 12 South African and 5 Belgian Reference Materials of igneous and (meta-) sedimentary origin are reported. These data have been obtained by Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES). For most samples, relative standard deviations are in the range 0.5–3% for major elements, 2–10% for minor elements, and equal to or better than 5% for the REE. Accuracies, as estimated from a comparison with recommended values, are about 10% or better.  相似文献   

14.
Three base-metal concentrates, each weighing 25 kg, were ground to -175 mesh (90 μm) and homogenised. They were then sub-sampled into foil-lined envelopes and sealed under argon before being issued to 27 participating laboratories for analysis. Over 4000 analytical results were returned and, after evaluation, a total of 37 elements within the three samples have been given recommended or more cautious probable values. The high standard of precision attained has enabled clear-cut distinctions to be made between methods for the determination of some elements. The most important of these is between titrimetry and electrogravimetry in the determination of copper.  相似文献   

15.
Analytical data on samples FeR-1, FeR-2, FeR-3 and FeR-4 obtained by instrumental neutron activation analysis and by inductively coupled plasma mass spectrometry are presented. The applied methods are described, and the analytical problems associated with their use are discussed. The accuracy of the two methods is demonstrated by comparing the results with the recommended values of the iron formation reference sample, IF-G. For the four FeR samples a set of values summarizing all data obtained by the two analytical methods is also given.  相似文献   

16.
Analytical data compiled on nine Geological Survey of Japan (GSJ) reference samples, "Sedimentary rock series" received by February 1996 are reported. After excluding outliers and examining critically the analytical procedures employed, the data were evaluated statistically. Recommended or preferable values for fifteen major and sixty minor and trace elements are proposed.  相似文献   

17.
Nine rare earth elements have been determined by inductively coupled plasma spectrometry (ICP) in eight USGS reference samples, MAG-1, SCo-1, SDC-1, BIR-1, DNC-1, W-2, BCR-1 and BHVO-1 and in the ANRT Glauconite, GL-O. Along with these new data, updated compilations are presented for these samples. Good agreement is observed between the present work and the compiled values.  相似文献   

18.
Two chromitite samples from the Isles of Shetland (North Scotland) have been processed, each in 200 kg quantities, as reference samples for the determination of gold and the platinum-group elements (PGE). One of these samples, Chromitite CHR-Pt+ is enriched in the PGE and the other, Chromitite CHR-Bkg has much lower concentrations. A detailed assessment of sample homogeneity is presented, together with the results of a cooperative study by thirty-five international geochemical laboratories, private and public. Contributed data together with derived working values are presented for Au and the PGE as well as for major, minor and a few trace elements. It is hoped that this first compilation report will encourage additional laboratories to participate in further studies of the PGE in these two CHR samples.  相似文献   

19.
A totally objective procedure involving sixteen statistical tests (a total of thirty four single or multiple outlier versions of these tests) for outlier detection and rejection in a univariate sample is applied to a data base of sixty four elements in a recently issued international geochemical reference material (RM), a microgabbro PM-S from Scotland. This example illustrates the relative importance and usefulness of these tests in processing modern geochemical data for possible outliers and obtaining mean concentration and other statistical parameters from a final normal sample of univariate data. The final mean values are more reliable (characterized by smaller standard deviations and narrower confidence limits) than those obtained earlier using an accommodation approach (robust techniques) applied to this data base. Very high quality (certified value equivalent, cve) mean data are now obtained for eleven elements as well as high quality recommended values (rv) for thirty three elements in PM-S. Earlier work using the accommodation approach failed to establish even one cve value for any of the sixty four elements compiled here. The present procedure of outlier detection and elimination is therefore recommended in the study of RMs  相似文献   

20.
Wavelength dispersive X-ray fluorescence spectrometry (WD-XRF) is widely used for the analysis of soils and sediments using well characterised procedures. However, difficulties can occur with samples such as unknowns containing small amounts of ore materials and samples collected from contaminated sites where trace elemental concentrations can exceed the concentration range for routine analysis. We studied the performance of a commercially available method, based on fundamental parameters (FP) to correct matrix effects. The spectrometer was originally calibrated with elemental or simple compound calibrants. Samples were analysed as pressed powder pellets. Eighteen sediment and soil reference materials, three of them with certified values for some of their constituents, were used to evaluate accuracy, by comparing results with recommended values and their standard deviations (RV ± 2s) or certified values and their confidence intervals (CV ± Cl). When results fell systematically outside these intervals, calibrations were refined with geochemical reference materials. The best agreement of results with recommended and certified values was obtained when the contents of H2O and C in each sample were included as matrix constituents during calculations. The detection limits of trace elements tended to be relatively high, because the measuring conditions employed were not maximised for sensitivity. The main advantage of the method tested was that it enabled the analysis of samples with high concentrations of trace elements and the determination of elements such as F, Bi, Sb and W, which are not commonly included in quantitative XRF analysis of geological samples.  相似文献   

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